Otimização multiobjetivo de pá de turbina eólica de eixo horizontal considerando aspectos aerodinâmicos e estruturais

Abstract

In recent years, wind energy has gained prominence due to its energy and environmental potential. Notable advancements have occurred in the sector, with wind turbines increasing their capacity from 75 kW to 7.5 MW. The main component of a wind turbine is the generator (rotor), responsible for converting the mechanical energy produced by the rotation of the turbine blades into electrical energy. The rotor blades, in turn, are essential structural components that need to be properly designed to ensure the efficient operation of the system and maintain its stability. It is in the context of improvements in the aerodynamic performance of the rotor, observing dynamic aspects of the natural frequencies of horizontal axis wind turbine blades, that this research is situated. Therefore, an approach for multi-objective optimization is proposed, addressing problems aimed at maximizing power and minimizing thrust, while imposing constraints on natural frequencies, associating them with limitations imposed by the turbine’s rotation. To achieve the objectives, the methodology involves coupling the aerodynamic model of blade element theory combined with actuator disk theory (blade element momentum theory - BEM) with the structural model of a rotating beam. In the proposed approach, the spar, associated with a material equivalent to composite, is treated as a simplification of the blade geometry. The standard NREL (National Renewable Energy Laboratory) 5 MW wind turbine is used as a case study, being optimized through five evolutionary algorithms. For each proposed optimization problem, the performance of each algorithm is evaluated, and turbine models from the Pareto front are extracted, with the assistance of the MCDM (multi-criteria decision making).